The subject matter of the present application relates generally to an electric starter motor. More specifically, the subject matter of the present application relates to a starter motor having variable rate dampening.
The application of diesel engines having a dual mass flywheel (DMF) has become more and more popular in the automotive industry due to environmental exhaust restrictions and the demand for smooth powertrain operation. To crank a diesel engine with a DMF, an electrical starter motor is subjected to very severe oscillation and impact since the DMF creates oscillation to the starter gear drive train. These oscillations and impacts can occur as either low frequency high impact loads, or high frequency low impact loads. These loads can cause pre-mature starter failure.
Starter motors with dampening members can dampen one or the other, but not both types of loads. Therefore, it is desirable to provide a starter motor that includes variable rate dampening members that will provide dampening for both high impact low frequency loads and low impact high frequency loads.